Calderon believes that it will be extremely difficult for Spurs to keep hold of their star asset now Bale has seemingly decided upon his future.
"You never know but when the player is willing to leave it is not easy to keep him when he wants to go.
"We had the same with Robinho when he wanted to leave in 2009. After that you just have to try and get as much money as you can.
"Spurs don't want the player to go, but it seems that the player has decided to leave, so it will be difficult.
"The figure being talked about is a huge amount of money."